The present invention relates generally to integrated circuits, and more particularly, to a power management module for an integrated circuit.
Integrated circuits (IC) include power supplies that provide different supply voltages to internal circuits of the IC. ICs further operate in different power modes including RUN, STOP, and STANDBY modes. A power supply also regulates the voltage and includes voltage regulator(s) for regulating the supply voltage to the internal circuits in the different modes of operation.
Switched mode power supplies (SMPS) are frequently used in ICs. An SMPS includes a switching regulator for providing a regulated supply voltage to the internal circuits. The switching regulator typically is designed to operate in a low bandwidth range (of the order of 100 KHz) as low bandwidth regulators are power efficient and cost-effective. However, such regulators often fail to sustain a sharp fall in current load of the IC that may occur, for example, due to partial/complete disabling of the IC, or transition of the IC from RUN to STOP/STANDBY modes. In such cases, the low bandwidth regulators prompt the IC to undergo a high voltage detect (HVD) reset due to slow response to the sudden changes in the current.
The IC is rebooted in the event of a HVD reset, which affects the system state and can lead to loss of critical data and time. In systems such as automotive systems, system state is critical and preferable not to lose system state due to frequent resets.
One solution to tackle the above-mentioned problem is to design a switching regulator that can sustain a sharp decrease in current consumption. One such conventional switching regulator includes a voltage detector and a signal generator. The voltage detector monitors the regulated supply voltage and the signal generator adjusts the duty cycle of the switching regulator if the regulated supply voltage increases beyond a predetermined threshold voltage. However, this switching regulator consumes a large area due to the additional circuitry required.
Therefore, it would be advantageous to have a power management module that efficiently regulates voltage in an integrated circuit, prevents the IC from a reset caused by sudden changes in current load, preserves system critical data, has a small area footprint, and generally overcomes the above-mentioned limitations of existing power management modules.